Resolve inconsistent use of `config.k8s.io` and `config.kubernetes.io`

[mortent]

We are not consistent in our usage of prefix for annotations. Some places we use config.k8s.io while in other places we use config.kubernetes.io. We probably can't remove support for any annotations that already exist, but we should decide on which one to use and make sure we always support it.

[mortent]

I suggest we standardize on config.k8s.io here, simply because it is shorter.
So all new annotation we add should use this format, and we should make sure all existing annotation also accept this format (possibly in addition to the long form since we don't want to break existing users).

[mikebz]

Can we possibly standardize on this in the next branch?